In the film days, filters were often used, an 81a or 81b to warm up an image a little. Graduated filters to bring down the exposure of the sky. Polarisers that cut glare and reflections, enhancing the colour.
Now with digital we can warm or cool an image with a few clicks. With the better dynamic range of todays sensors we can use graduated filters in software.
There are times that filters can still be useful. In this image I used a polariser to enhance the colour and a neutral density filter to slow down the shutter speed to a few seconds. This blurred the sea and made many of the people on the pier disappear.
If you photograph moving water, try using a neutral density filter shoot from half a second to about a minute and look at the results to find the shutter speed you prefer.